Magnet for alternating currents.



No. 878,402. f' PATENTED FEB. 1,A 1908. GQ KRAMER.v

MAGNET FUR' ALTERNATING GURRENTS. APBLIGATION FILED MAR. 12. 19o6.

CHRISTIAN KRAMER, OF IFRANKFORT-ON-THE-MAIN, GERMANY, ASSIGNOR TO FELTEN &

GUILLEAUME LAHMEYERWERKE ACTIEN GESELLSCHAFT, OF FRANKFORT-ON-THE MAIN, GERMANY.

MAGNET FOR ALTERNATING- CURRENTS.

To all whom t may concern:

Be it known that I, CHRISTIAN KRAMER, a subject of the German Emperor, and a resident of Frankfort-on-the-Main, Germany, have invented certain new and useful Improvements in Magnetsfor Alternating Currents, of which the following is a specification.

The present invention relates to improvements in alternating current magnets and the obj ect of the invention is to` rovide'a magnet of this character which shall be particularly applicable for use with brakes employed in connection with electric hoists, railways, etc. Single phase alternating current magnets provi ed with two windings through which currents of different phase are conducted are Well known, but the means used for displac- -lng the` phase, such as throttling coils, cause .of' small phase displacement,

a considerable loss of energy.

One of the objects of the present invention 1s to so construct such a ma necessary to have a multip tem nor to provide a s phase in the winding of t 1n external resistances so energy caused by such'arran ements as have heretofore been employed w' be avoided.

The present invention is illustrated diagrammatically in the accompanying drawing, referring to which isia single phase alternating current ma net having a coil h wound on the core d an connected in series with a motor b and linea. The magnet is also provided with a shunt windingfn. wound on two other cores f,f2 and connected with the winding h and line, as indicated.

The winding 'n it will be seen is connected in parallel with the translating apparatus, and the main current winding h lies in a circuit while the other Winding n, owing -vto its self-induction, is in a circuitof greater phase displacement.

The increased self-induction, resulting from the arrangement of the winding illustrated in the drawing, prevents the starting current from exceeding l a predetermined strength and the series current through the Winding h presents a considerable phase` difiase feeding sy ecial character of e magnet itself or Specicaton of Letters Patent. Application filed March l2. 1906. Serial No. 305.720.

et that it is not that the loss of Patented Feb. 4, 1908.

ference over the current in the shunt, or pressure, winding n so that instead of the magnet having an oscillating field, as do the alternating current magnets commonly em-.

necessary'to create an artificial phase difference in the winding of themagnet or to use an external resistance such, for mstance, as

is described in German Patent 149,589. The

arrangement described vin saidpatent involves a considerable loss of which is obviated by the present invention.

An important feature of the present invention is that the main and shunt windings are wound on different poles or portions of the magnet.

Having thus described the invention, what is claimed iszn I. The combination with a source of single phase-alternating current,'of an electro magnet comprising a core consisting of three paralle l pole pieces and a yoke connectin the same, and windings u on said pole pleces, the Winding upon one o connected in series across said source with a substantially non-phase-displacing, currentreduc` means, the windings upon the other two pIdIe pieces being connected in series across said source.

2. The combination with a source of single phase alternating current, of an electro magnet comprising acore consisting of three parallel pole piece's'and a yoke connecting the same, and windings upon 'said pole pieces, the winding upon one of s aid pole pieces being connected in series with a motor across said source, the windings upon the other two pole pieces being connected in series across said source.

In testimony whereof I have signed my name to this specificationin the'presen'ce of two subscribing witnesses. CHRISTIAN KRAMER. Witnesses:

FRANZ HAssLAcHER, ERWIN DiPPEL.

said pole pieces being electrical energy 

